Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, a type coercion issue in a post actions API endpoint allowed non-staff users to issue warnings to other users. Warnings are a staff-only moderation feature.
The vulnerability required the attacker to be a logged-in user and to send a specifically crafted request. No data exposure or privilege escalation beyond the ability to create unauthorized user warnings was possible. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch.
No known workarounds are available.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 3
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Discourse Discourse
cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
|
2026.1.0
|
2026.1.2
|
|
Discourse Discourse
cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
|
2026.2.0
|
2026.2.1
|
|
Discourse Discourse
cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:*
|
— | — |
References 4
https://github.com/discourse/discourse/commit/60a588f4da4ab0feceb2c44787d4261b4…
security-advisories@github.com
https://github.com/discourse/discourse/commit/d3cb203feabc46d765ecb91f348613a2b…
security-advisories@github.com
https://github.com/discourse/discourse/commit/f5fef73827da7520efc517357bd2a6bab…
security-advisories@github.com
https://github.com/discourse/discourse/security/advisories/GHSA-xq37-5fvf-4m4j
security-advisories@github.com